Ok. I see a BL change for my site on some of the DCs you mentioned.
But I'm surprised!
The "updated" BL number resembels that of which was noticed on 64.233.187.--- during last month (August 2006).
Surpsrised because at that time GoogleGuy wrote about it [webmasterworld.com] :
It's Brett's decision to call something an update, but I agree this one isn't anything to write home about. Like Pluto, I think this would be a shrinking update; the SERPs aren't really changing. :)
I talked to one of the engineers who would know, and it turns out that it's an engineer who has grabbed the 64.233.187.whatever datacenter for himself to tinker around with making info: queries slightly more accurate. I don't expect the visible/external info: or backlink data to spread to other data centers (or if it did, not for a long time).
So have fun poking around over there if you really enjoy monitoring IP addresses, but just bear in mind that it's an engineer tinkering by himself, not part of a larger trend or an upcoming update.